去应力退火对TC18和TC21钛合金吸氢含量的影响

Effect of stress relief annealing on hydrogen absorption of TC18 and TC21 titanium alloy

在井式空气炉内按GJB 3763A—2004标准的最高温度和最长保温时间对TC18和TC21钛合金进行了去应力退火,研究了空气炉去应力退火对TC18和TC21钛合金吸氢含量的影响。结果表明:与去应力退火前相比,TC18钛合金经空气炉去应力退火后氢含量有所增加,而TC21钛合金氢含量反而降低。经去应力退火后,TC18和TC21钛合金的氢含量分别为0.0029%和0.0025%,远小于材料规范要求的氢含量(<0.015%);随表层至中心(深度变化),氢含量未见明显的规律性变化,里层氢含量与表层氢含量相差不大。从吸氢量考虑,该两种钛合金均可采用空气炉进行消除应力热处理。

Stress relief annealing of TC18 and TC21 titanium alloys was carried out in a pit-type air furnace according to GJB3763 A-2004 standard with the highest temperature and longest holding time,respectively.The effect of stress relief annealing on hydrogen absorption of TC18 and TC21 titanium alloys was studied.The results show that the hydrogen content of TC18 titanium alloy increases after stress relief annealing in air furnace compared with that before stress relief heat treatment,while that of TC21 titanium alloy decreases.The hydrogen content of TC18 and TC21 is 0.0029%and 0.0025%respectively,that is much lower than that of required by material specifications(<0.015%)after stress relief in the air furnace.After stress relief annealing,the hydrogen content of TC18 and TC21 titanium alloys change regularly with the change from surface to center(depth),and there is little difference between the hydrogen content of inner layer and that of surface layer.Considering the amount of hydrogen absorption,stress relief annealing can be conducted for the two titanium alloys by air furnace.